Download
Overview
Standard installation options
The latest stable version is 4.1 TBA (release notes).
Windows
The Windows package is based on Python 3.13 for 64 bit systems. The installer and .zip packages are identical, except for the installation. Most people download the installer package (green button).
Standard Windows installer (.exe)
Standard Windows no installation required (.zip)
OpenSesame is developed and tested on Windows 11. Your mileage may vary on other versions of Windows.
Mac OS
Mac OS packages are not yet available for OpenSesame 4.1. The download link below still points towards 4.0.
Linux / Ubuntu
Copy-paste the line below into a terminal. This will download and run an installation script. The installation script requires curl and virtualenv. On Ubuntu these can be installed with sudo apt install curl python3-venv.
bash <(curl -L https://github.com/open-cogsci/OpenSesame/raw/refs/heads/4.1/linux-installer.sh) --install
OpenSesame is developed and tested on Ubuntu 24.04. Your mileage may vary on other Linux distributions and other versions of Ubuntu.
Advanced installation options
PyPi (crossplatform)
All packages can be pip-installed. Note that OpenSesame is called opensesame-core on PyPi.
OpenSesame core dependencies:
pip install --pre opensesame-core opensesame-extension-sigmund opensesame-extension-osweb opensesame-extension-updater opensesame-plugin-psychopy opensesame-plugin-media_player_mpy pygame
PsychoPy for the (default) psycho backend. Depending on your operating system and version of Python, PsychoPy may not install properly. If this happens, seek help on the support forum or use one of the premade packages/ installers.
pip install psychopy psychopy_sounddevice psychopy_visionscience
PyGaze for eye tracking:
pip install https://github.com/smathot/PyGaze/releases/download/prerelease%2F0.8.0a3/python_pygaze-0.8.0a3-py3-none-any.whl
Expyriment for the xpyriment backend
pip install http://files.cogsci.nl/expyriment-0.10.0+opensesame2-py3-none-any.whl
Once you have installed all packages, you can simply run OpenSesame by running:
opensesame
Or for Sigmund Analyst (code editor):
sigmund-analyst
Anaconda (cross-platform)
First, create a new Python environment for OpenSesame (optional)
conda create -n opensesame-41 python=3.13
conda activate opensesame-41
Next, follow the PyPi installation instructtions above. Dedicated Anaconda packages are no longer provided.
Older versions
Older versions can be downloaded from GitHub releases:
Source code
The source code of OpenSesame is available on GitHub.
Tips
Which version of Python to use?
OpenSesame is currently built and tested with Python 3.13. Others versions of Python >=3.10 work but are not extensively tested. Python 2 is no longer supported. The last release that included a Python 2 package was 3.3.12, which can still be downloaded from the release archive.
When (not) to update?
- Update while developing and testing your experiment; it is always best to use the latest version of OpenSesame.
- Do not update while running an experiment; that is, do not update while you are collecting data.
- Run an experiment with the same version of OpenSesame that you used for developing and testing.
Manually upgrading packages
OpenSesame is a regular Python environment, and you can run pip install commands in the Jupyter console.
Tips for system administrators
- When a new major version of OpenSesame is released (with a version ending in 0, e.g. 3.1.0), it is generally followed quickly by one or two maintenance releases (e.g. 3.1.1 and 3.1.2) that address major bugs. Therefore, if you are installing OpenSesame on systems that you do not update often, it is best to wait until the second or third maintenance release (e.g. 3.0.2, 3.1.3, etc.). That way you minimize the risk of rolling out a version of OpenSesame that contains major bugs.
- The Windows installer allows you to silently install OpenSesame using the
/Sflag.